spoon mu itr

Alright guys before the "go search noob" post begins i did a lot of reading and out of 30 pages of search i didnt find what i needed.

The 94-99 GSR has different exhaust lengths than every other USDM integra.
That means 94-01 integra ls/rs/gs and 00-01 gsr and USDM itr have no dimensional differences.

How about the JDM type r?

I am currently running with the JDM 4-1 header and JDM cat.

Does it need any mods if I put a USDM LS catback exhaust on it? or it's direct bolt on?

Thanks

Tyrant_007

iTrader: (1)

The flow rate of the ITR is supposed to be 30% greater than the GSR from what I've read in the past. I think the muffler is just a higher capacity muffler.

USDM catbacks are shorter than the JDM models. This is due to the fact that the JDM exhaust manifold and the cat are shorter. It's best to use all JDM exhaust parts or all USDM if you want to use all OEM Honda parts. When people mix (such as JDM manifold, and USDM catback, they usually get a custom made Cat to accomodate the difference in length.

spoon mu itr

Thanks

I thought the JDM cat is shorter than USDM's because the JDM 4-1 header has the longer lengths than the USDM 4-2-1.
So the lengths of JDM and USDM catback are the same.
I was planning to get a greddy se exhaust for my integra but I will go for a JDM exhaust now.

94eg!

iTrader: (2)

No the JDM cat is shorter and the exhaust pipe is longer to meet it. Collector length is the same. The JDM cat only has one brick inside while the US cat has two. This is why they are different lengths.

jahraul

Need your help everyone:

Looking to do JDM ITR Headers with USDM ITR full exhaust (b-pipe and muffler) on my 99 GSR Coupe.

Goal is to have more hp with that quiet sleeper look.


What do you all think?


OR Should I go with JDM ITR headers with JDM ITR full exhaust?


What are the exhaust size differences between JDM ITR vs. USDM ITR?

TIA!

Tekkaboy

iTrader: (2)

JDM ITR header is 2.5", USDM is 2" (or 2.25", I forget). But if you put the smaller USDM cat-back on the JDM header, you are defeating the purpose of having a larger diameter header. Exhaust size should always increase or stay the same as you get farther from the engine.

Dave-ROR

Ideally yes, but I gained over 8whp/6ftlbs with the JDM ITR header and a carsound (POS!) cat still with a stock GS-R catback so I wouldn't say that you are defeating the purpose completely.

I'd suggest JDM ITR header, some 2.5" high flow cat, and a fixed (remove the stepdown piece going to the flange) USDM ITR exhaust though if you want to keep it stock/sleeper.

94eg!

iTrader: (2)

Just buy the full Japanese exhaust from a place like H motors. You can get the cat, b-pipe and muffler. If you want stock look/sound, then this is the best "stock" option.

jahraul

hey they only have the jdm itr headers available i didnt see the exhaust at all



I guess ill go with JDM ITR headers, JDM ITR B pipe, and JDM ITR exhaust on my 99 GSR to keep that low key stock look with the benefit of more HP . Am I missing anything in regards to the "full exhaust?"


On a side note, anyone know for a fact the exhaust size for OEM USDM ITR? I saw that someone stated earlier that the JDM is 2.5, vs USDM 2 or 2.25?


TIA!

jahraul

Do you have any pics of your setup or where you purchased it from?

With your "suggestion" (JDM ITR header, 2.5" high flow car, USDM ITR exhaust...wouldnt it be more beneficial to get the JDM exhaust?

Dave-ROR

Well I got my USDM ITR exhaust for free, soo.. I'm not sure how much difference (performance wise) there is between the USDM and JDM exhaust. Personally I doubt it's very much, if any..

I'd go with whatever you find the cheapest, just get that before the high flow cat or test pipe (depending on which you want) since the exhaust choice (JDM length or USDM length) will determine the cat or test pipe length.

Pics.. probably, this was 2001 or so, although the same setup is currently on my 97R. I purchased it from a shop that's long gone (Trey's old business, Trey owns itrexpo.com and itrca.com).

Oh yeah, SMSP makes a good test pipe in whatever length you decide on if you want a test pipe, assuming Dave@SMSP is still around.. not really into modifying these cars too much these days..

jahraul

thanks for the great info!

do you know the exhaust size difference between the USDM ITR vs JDM ITR?

Dave-ROR

I do not know the length difference, sorry.

jahraul

sorry not the length, I meant to ask the diameter differences?

Little_Nolan

iTrader: (3)

Diameter of piping is the same as far as I know.. pretty sure the JDM Bpipe has the step down section just like USDM.

Differences are: Cat and header collector is 2.5" on JDM exhaust and B pipe is longer to fit the shorter cat.

jahraul

ok cool just trying to figure out which full exhaust for my 99 gsr

full oem itr usdm headers w/ full exhaust VS. full oem itr jdm headers w/ full exhaust

Thanks for the info!

DOHCTA

sorry to bring this thread btl but I'm wondering if an '01 gsr axle back will mount up to my '98 gs midpipe. Are the diameters the same?

DOHCTA

DOHCTA

it's all usdm, other than the front end.

Dave-ROR

For that question the regular Integra forum might be best as I'm not sure many here have measured a GS bpipe or a GS-R axle back. I've never even see a GS catback.